Maxim Integrated Products (Sunnyvale, CA) offers the MAX44000, a digital ambient-light and infrared proximity sensor that detects light like a human eye. Designed using the company’s proprietary BiCMOS technology, the IC integrates three optical sensors, two ADCs, and digital functionality into a 2mm x 2mm x 0.6mm package.
The MAX44000 consumes just 5μA when the ambient sensor is enabled, and 7μA when both the proximity sensor and ambient light sensor are activated. Once a sensed signal is received, it is run through a DC ambient, infrared (IR) rejection front-end circuit and sent to an ADC. The process allows the MAX44000 to operate in the presence of large amounts of DC IR radiation. By using a single-pulse technique for pulsing the external IR LED, the sensor is immune to fixed-frequency external IR radiation.